A packinghouse is a facility where goods, such as fruit and vegetables, are received and processed prior to distribution to market. In the typical packinghouse, the goods are first received and then sorted based upon several factors, for example, size and quality grade. Once sorted, the goods are moved through the packinghouse via conveyor belts for downstream processing, such as labeling and packaging.
One example of downstream processing for fruits and vegetables sorted for direct sale is the application of wax to the exterior of the product. Advantageously, the wax provides a barrier for aiding in maintaining the internal moisture of the fruit or vegetable. Additionally, the wax may inhibit mold growth, protect fruits and vegetables from bruising, prevent other physical damage and disease, and enhance appearance. In short, the application of the wax keeps the fruit or vegetable in good shape during transit to the final point of sale, for example, a supermarket.
As is typical in the packinghouse, the fruits and vegetables are processed in large numbers and relatively quickly due to the perishable nature of the product. Accordingly, manual application of the wax to each fruit or vegetable is impractical and onerous. One approach to this concern is machine driven wax applicators.
For example, U.S. Pat. Nos. 2,821,957 and 2,903,995 to Fitzgerald disclose a device for applying wax to fruits and vegetables. The device includes an endless conveyor belt, and a plurality of brushes above the conveyor belt. The conveyor belt receives the fruits and moves them down a longitudinal path. The device includes a wax reservoir above each brush that periodically dispenses wax directly on the brush.
Another approach is disclosed in U.S. Pat. No. 5,101,763 to Creason et al., which also discloses a fruit wax application device. This device includes a two-stage wax application process, the first stage depositing a fungicide and wax mixture on the fruits and the second stage depositing a second layer of wax on the fruits. The device includes a brush bed conveyor for moving the fruit down a longitudinal path past a pair of spray assemblies.
Yet another device is disclosed in U.S. Pat. No. 6,153,253 to Affeldt et al. This device includes a brush bed conveyor for moving the fruit down a longitudinal path, a pair of controlled spray nozzles for coating the fruit with wax, and a camera for capturing images of the fruit. The device also includes a controller for configuring the spray nozzles to selectively spray each fruit based upon detected characteristics of the fruit, for example, size.
U.S. Pat. No. 2,738,761 to Gerwe, assigned to the present application's assignee and the contents of which are incorporated by reference in their entirety, discloses a fruit wax application device including a plurality of brushes, and a plurality of rollers for conveying the fruit down a longitudinal path under the brushes. The device includes a wax spray nozzle above the brushes for dispensing the wax thereto.
U.S. Pat. No. 2,412,686 to Kalmar, assigned to the present application's assignee and the contents of which are incorporated by reference in their entirety, discloses a fruit wax application device including an endless conveyor of rollers for moving the fruit down a longitudinal path. The device includes a spray nozzle for applying a coating of wax to the fruits as they pass through the endless conveyor.
Of course, in each of the above devices, the fruits and vegetables being conveyed were substantially round in shape, for example, oranges, potatoes, etc. Fruits and vegetables having such a shape are more readily conveyed throughout the packinghouse. Nonetheless, some fruits are not so readily conveyed in the packinghouse, for example, the pineapple including the oblong body portion and the lengthy crown/stem part.
More specifically, the aforementioned wax application process may be problematic due to the shape of the pineapple. Accordingly, the application of wax coatings to pineapples is typically performed via a flooding process. The flooding process may have several drawbacks though. For example, the flooding process may not be efficient as a significant amount of wax is consumed to flood the pineapple. Because of this inefficiency, the typical wax flooding process includes a recapturing element for recycling the used wax. Nevertheless, the recycled wax may include contaminants, such as dirt and pests. Moreover, the recycled wax may lose potency due to unintended dilution during the recapturing process. Also, the flooding process may provide little to no control on the application of wax to the pineapple.